Template follower



Sept. 20., 1938.

J. L. ANDERSON TEMPLATE FOLLOWER Filed July 10, 1937 INVENTQR A VATTORNEY Patented Sept. 20, 1938 PAT ENT" 6F I CJE I TEIVIPIJATE'FOLLOWER.

James L. Andersonpclosteni N. J., assignor to AirLReduction Company,Incorporated, I New York, N Y.-,

a corporation of New-York Application-July 10, 1937, Serial No. 152,958

17-- Claims; (Cl.:3323) inventionrelates to terripl'ate followers.

It*i'sanobj'ec't of the invention'to. provide an"improved;template-follower which automatically follows"ternplates'- ofirregular .shape' including curves-"of rela'tively' "short" radii. Theinvention comprisesnovel features"and combinations of" elements whichmake the template-follower simple and -econoinical to manufactureandconvenient to use.

In a'ccordancewith onefeatur'e of theinvention a followerrolleroiraninclined axis rests on the top face-of a-templat'e and isdriven to cause it to travel along thetemplate; andguide meansare-provided"for 'causing the" follower roller to stay*-on=' me-- topface" of 1 the template around curves-in eitherdirection as wellas alongstraight run's Another objectof theinvention" isto prevent the guidemeans from' binding against the side's' o'f t e"=tem'plate"o n"sharpcurves.

Othe'r oh ct's,*fea'tnres and advantages of the inventionwill appear 'or-be pointe'd out as the speeification proceeds.

In the accompanyingdrawing', forming part Fig;- 1 i's as'ectibnal viewof a template-follower emliiodt ihg the inventionr c "is an elevation ofthelowerpart of the template -follower of' Fig. 1, looking toward the"to Fig?" 'biitshowing a'modified"form of the invent'io Fig'si l and 5 amelevations of other modified forms of the invention.

bracket :l Q'iwi'th a -s'crew -I l barlc'fl'niof machines 1 for clampingit to a avin' foldi-n'g parallelogram frames the torch is s'upportedfr'om theiront-bar and partakes of the same mover-menta's atracer ortemplate-follower clamped to the bar. The inventionristnoh 'limit'ed' to-machlnes of the foldingsleeve rlfi 'isfreekto slide up'and down in'thebearing ilfi-"for a limited distance butis prevented frOn-i turningIcyiarack I! which is fastened to thesl'eeve by'scre'ws I8 and extendsinto a slot'l'9 in the bracket ID. This slot is inefiect a keyw'ay'andthe rack IT a key to prevent the sleeve-from: rotating, buttheslotI9 is longer Fig. :3 is 'a---frag-mentary* sectional view similaruniversal cutting machine." With than the rack so that the sleeve canmove up and downa ,A pinion, 2d,. on an axle 22 rotated, by ahandwliee'l' 23',lmeshes With the rack I T and serves to" loweraridfraise thesleev'e I51 when the'template-fcnower ist'o be moved into orout. of Contact withia template. The upper part of thet'e'mpla'te-follcrv've'ris similar to known tracers andaidescript'ioniof itis'not necessary'fora c'omplet'ei understanding ofthis" invention; Tracers of suchfconstructi'onlar'e'zshown in Patent No.2,059,755; dated November 3, 1'936;.and Patent N0. 1,999,'5,"dated April30, 193 5.

The lower end of the sleeve i5 is of reduced diameter andextends'iint'oa housing or frame 25. 'Theupper end of theirame 25 has a slopingannular. faceviihi'c'h contacts with an undercut shoulderZBon'the'sl'eeve; The housing or frame 25 rotates on .thesleev'e l5 as abearing and the outs'ideof the upwardly] extending end of the frame25*fo'rms a continuation of the outside surface of the'sl'e'eveil'5which s'lides'in the bearing'l' v'i During" operation" of thetemplate-followerthesle'eve l 5=and"frame M are free to move up anddo'wn with afloating'action'inresponse'to anyirregularities in thesupporting surface along whi'chthe template=follower runs?A-'ternplate-follower roller 2'l. is secured to the end 'of aslopingaxle 28"that rotates in anti-' frictioirbearings" 29;3011'eld bythe frame 25.? A bevel gear 32 keyed to the axle 28 near its upper endmeshes" with a bevel gear 33 fastenedto" the lower end" of" drive' shaft35:

The frame 25' a'nd"sleevel 5 are 'held assembled by ai-collar 3 6bn the"drive shaft "351 Thiscollar supportsa bal libearing' 33 inwhich theshaft 3 5'. turri's and-"the ball' bearing thrusts against a shoulder 34lathe-frame 2'5 and keeps the'upper'" end' 'of"-the"framein"coritact; orsubstantially. so, with the undercut" sho'uld'e'r' "26 "of' the sleeve;

The xis-cf rotation of the'frame 25 about the sleeve 6'5"iscoihcident'with"theaxis of the drive shaft 35, and the pointoftractionof the roller 21 on-a'te'mmate -3lisin line wit'htheaxisof theshaft? 35.- Y

The roller 21' is prevented-from running oiT the. top face ofthetemplate 37by'guide means which includesa'lowerguide roller '39, atv theend of the anew in position 'to*contact withone side of the template,and two other: guide rollers or" wheels that contact with'the otherside? of the" template. The guideroller. 39"is'pre'ferably in"-.tegrarwith'the roller 21 and axle 28'but ma -pa an idler rotatableindependently. of the roller 21; andaxle '28i' Inan'y' event someslippage of the peripher'yo'f the guide roller 39 on the side' of theCir template will occur because the different points on the surface ofthe guide roller are not equidistant from its axis of rotation andtherefore travel at different velocities when the guide roller turns.This slipping is not objectionable, however, because the guide rollerdoes not support the weight of the template-follower and has relativelylight contact with the template.

The wheels 49 are preferably idlers and are supported by screws 4| froma swivel member 42 which turns about a vertical screw 44 threaded intothe oblique bottom face of a rod 45. That part of each of the screws 4|just above the head of the screw comprises the axle for the wheel 40supported by that screw, and the large fiat head of each screw 4| servesas the thrust bearing which supports the weight of the wheel 4!). Rotarymeans driven by power can be employed in place of the wheels 40, but theadditional traction obtained in this manner is unnecessary with mostmachines on which the template-follower of this invention is used.

The rod slides longitudinally in an inclined bore in the frame 25 but isprevented from turning by a pin 41 which is fixed to the frame 25 andextends through a slot 48 in the rod 45. A coil spring is pressedagainst the upper end of the rod 45 by a screw 5| which threads into theupper end of the bore in which the rod 45 slides. The pressure of thespring 50 yieldably holds the wheels 40 against the side of thetemplate, and the reaction of the spring against the screw 5| actsthrough the frame 25 and urges the guide roller 39 against the template.

.One of the wheels 40 contacts with the template a short distance aheadof the point of traction of the roller 21 on the template, and the otherwheel 40 touches the template some distance behind the point oftraction. The distance between the wheels 40 is made short so that thetemplate-follower can turn curves of short radii. The spring 50 makes itpossible for the wheels 40 to move either way, depending upon whetherthey are on the inside or outside of a curve, to allow for the curvatureof the arc of the template between the Wheels 40. The guide roller 39has line contact with the template along a vertical line and thereforedoes not bind when passing around sharp curves, as is the case withordinary flanged wheels.

A slight speeding up or slowing down of the template-follower of Fig. 1occurs when it turns sharp curves because of the epicyclic effect whenthe gear 32 rolls around the driving gear 33. The epicyclic effectcauses the speed of the templatefollower to increase when the gear 32rolls in the same direction that it is turning, and to slow down whenthe gear rolls in the opposite direction. This variation in speed is notenough to be objectionable with ordinary work, but when very uniformspeed is essential it can be obtained with the structure shown in Fig.3.

The upper, broken away portion of the template-follower shown in Fig. 3is the same as that shown in Fig. 1, but in Fig. 3 a frame 25' isslightly different in shape from the frame 25 of Fig. 1 to allow for adifferent location of bearings. Wheels 41' are supported from. a swivelmember 42 at the end of a rod 45 which slides in the frame 25. The partsin Fig. 3 that correspond with parts in Fig. 1 are indicated by the samereference character with a prime appended.

A worm 54 at the lower end of a drive shaft 35' drives a worm gear 55secured to a shaft 56 journaled in the frame 25'. A bevel gear 58 on theshaft 56 meshes with a gear 59 at the upper end of an axle 28' totransmit rotation of the shaft 56 to the axle 28'.

Ball bearings 29 and 30' hold the axle 28' at an inclination and thereare a traction roller 21' and a guide roller 39' at the lower end of theaxle. When turning sharp curves with the modified form of the inventionshown in Fig. 3 there is substantially no epicyclic effect to increaseor decrease the speed of the roller 21'. If the frame 25 makes a turn ofninety degrees, the only movement of the gear 58 caused by the turningis a rotation through an angle corresponding to onequarter of thedistance between teeth of the worm gear 55, and the angular movement ofthe rollers 21 and 39 is only slightly more, depending on the ratio ofthe gears 58, 59.

Fig. 4 shows a modified roller assembly which makes it unnecessary tohave the wheels 40 to keep the traction roller on the template. Inaddition to a traction roller 52 and a guide roller 63 corresponding tothe rollers 21. and 39, re-

, spectively, of Fig. 1, another guide roller 65 is connected with theaxle in position to contact with the side of the template remote fromthe roller 63. Since the guide roller 53 prevents the traction roller 62from running off the template ,to the left and the guide roller 65prevents the traction roller from running off to the right, the wheels40 are no longer necessary.

Fig. 5 shows a template 69 which has a groove along its top face, and atraction roller H runs in this groove as shown in the drawing. Thisgroove gives the roller greater friction contact with the template, andit keeps the roller from being displaced laterally of the template whenthe follower is not in operation. When the roller H is driven to causethe follower to travel along the template, the frame and other structureto which the template-follower is connected and for which it furnishesthe motive power has friction in its bearings and offers resistance tothe movement of the template-follower. As a result of this resistancethe .gear 32 (Fig. 1) tends to ro-g tate around the driving gear 33 toturn the frame 25 about its axis. Such a turning of the frame wouldcause the roller H (Fig. 5) to climb out of the groove in the template69, but such movement of the traction vrolleris prevented by a guideroller 13 which is similar in construction to the guide rollers 39 and63 employed with the embodiments of the invention shown in Figs. 1 and4. I

It will be understood that terms of orientation used in the descriptionand claims are relative. The invention is not limited to the embodimentsillustrated and some features can be used without others withoutdeparting from the invention as defined in the claims.

I claim? 1. A template-follower for a universal cutting or weldingmachine including in combination a roller for contact with a template,an axle about which the roller turns, said axle having a substantialinclination so that the roller tends to travel transversely of thetemplate, a frame holding the axle, and a bearing on which the framerotates, about an axis in line with a point of contact of the roller onthe template, to change the direction of travel of thetemplate-follower.

2. In a template-follower, a frame rotatable about a vertical axis tosteer the template-follower, anaxle carried by the frame, a roller onthe axle in position to contact with a template at a point in line withthe axis of rotation of said frame, the axle being at a substantial,acute guide roller connected with the first roller in posi-' tion tocontact with a side of the template when the first roller is operatingalong the top. face of the template. a

3. In a template-follower,a frame and a bearing on which the frame turnsas the template follower changes its direction of travel, an in clinedaxle carried by the frame, a template-follower roller on the axle inposition to contact with the top of a template at a pointin'line withthe axis of rotation of the frame, a second roller on said inclined axlein position to contact with one side of the template and serve as aguide to confine movement of said template-follower roller transverselyof the top face of the template, and means for holding the second rolleragainst the template.

4. In a template-follower, a frame and a bearing on which the frameturns as the templatefollower changes its direction of travel, aninclined axle carried by the frame, a template-follower roller on theaxle in position to contact with the top of a template at a point inline with the axis of rotation of the frame, and two guide rollers onthe axle in position to contact with opposite sides of the template toprevent displacement of the template-follower roller transversely of thetemplate.

5. In a template-follower for cooperation with a template having alongitudinally recessed top face, a traction roller having a face whichfits into the recess of the template, an axle for said traction roller,the axle being inclined with respect to the template so that thetraction roller tends to climb out of the recess toward one side of thetemplate, and a guide roller connected with the traction roller inposition to contact with the other side of the template to prevent theroller from moving out of the recess.

6. A template-follower including a traction roller which runs on the topface of a template, a guide roller attached to the traction roller inposition to contact with a side of the template and prevent transversedisplacement of the traction roller, and yielding means which hold theguide roller against the template.

7. A template-follower including a traction roller which runs on the topface of a template,

a guide roller attached to the traction roller in position to contactwith a side of the template and prevent transverse displacement of thetraction roller, a second guide roller which contacts with the otherside of the template, and yielding means for urging said second guideroller against the side of the template.

8. A template-follower including a traction roller constructed andarranged to travel along the top face of a template and having a guideroller directly connected with the traction roller and located inposition to contact with one side of the template at a set distance fromthe traction rollerytwo wheels in positions to contact with the side ofthe template away from the guide roller at points slightly ahead of andslightly behind the line of contact of the traction roller and its guideroller with the template, and means urging the wheels toward the guideroller to hold said wheels and guide roller in contact with oppositesides of the template.

9. A template-follower comprising a frame, an axle carried by the frame,a traction roller on the axle in position to contact with and travelalong the top face of a template and having a guide roller attached tothe traction roller in position to contact with one side of thetemplate, two wheels :in positions to contact with the side of thetemplate away-from the guide roller at points slightly ahead of andslightly behind the lineof contact of the tractionroller and its guideroller with the template, a support for said wheels,

and a swivel connection between said support and the frame.

10. In a template-follower, a vertical drive shaft, a frame, a bearingonwhich the frame turns about the axis of the drive shaft, an inclinedaxle in the frame, a template follower roller on the axle with the lowpoint of the roller in line with the axis of rotation of the frame,

said axle having a substantial inclination sothat the roller tends totravel transversely of the template, guide means for preventingtransverse movement of the roller on the template, and motiontransmitting connections between the drive shaft and the roller.

11. In a template-follower, a vertical drive shaft, a frame, a bearingon which the frame turns about the axis of the drive shaft, an inclinedaxle in the frame, bearings in the frame in which said axle rotates, aroller secured to the axle at a location which puts the lowest point ofthe roller in line with the axis of rotation of the frame, said axlehaving a substantial inclina tion so that the roller tends to traveltransversely of the template, guide means which prevent the roller fromrunning transversely and which hold said roller on the top surface ofthe template, and gearing connecting the drive shaft with the axle.

12. In a template-follower, a vertical drive shaft, a frame, a bearingon which the frame turns with respect to the drive shaft and about theaxis of the drive shaft as the templatefollower changes its direction oftravel, an inclined axle in the frame, bearings in the frame in whichsaid axle rotates, a roller secured to the axle at a location which putsthe lowest point of the roller in line with the axis of rotation of theframe, said axle having a substantial inclination so that the rollertends to travel transversely of the template, guide means which preventthe roller from running transversely and which hold said roller on thetop surface of the template, and gearing connecting the drive shaft withthe axle, said gearing including a worm on the drive shaft operating aworm wheel which has its axle supported by the frame.

13. A template-follower including a traction roller supported forrotation about an axis which has a substantial inclination, means formaintaining the roller in contact with a template and the incline of theaxis in a definite relation to the template, said incline beingsufiicient to make the roller tend to move transversely of the template,and apparatus for driving the traction roller.

14. A template-follower including a frame, a bearing on which the frameturns about a substantially vertical axis, an axle held in the frame, atraction roller on the axle constructed and arranged to contact with atemplate, said axle having a substantial inclination so that the rollertends to travel transversely of the template,

means holding the traction roller against trans means connected withythetraction roller for.

rotating 'said roller.

,:115.'A template-follower including a frame, a

bearing onwhich -the frameturns about .a sub-- 1 stantiallyvverticalaxis, an inclined axle held in the frame, roller means on the axle inposition to contact with a supporting surface and with from turningexcept'in accordance with turns in the template.

16;.An automatic template-follower including aroller having afacewhichbears against a guidinglsurface of a template,and having a friction face:constructedland arranged to bear against a surface which'isat aninclination to the axis of rotation of the "roller to produce a tractiveforce having a component toward the'guiding surface of the.template,.and power means for rotating the roller.

1'7. In a template-follower, an inclined axle, and a roller on=the axlewith two contact faces in such relation that one face rolls along anupstanding guidingxedgeof a template while the other l-faceisupports theroller from a substantially horizontal surface and supplies tractiveforce to the template-follower with a component of the tractiveforoem'ging the roller toward. the guidingedge of the template.

JAMES L. ANDERSON.

